Participation in the cooperative clinical trials of the Southeastern Cancer Study Group: Phase 1 studies: initial studies of toxicity of new drugs, new schedules of dosage or new combinations of drugs. Phase 2 studies: non-randomized studies of the effectiveness of a specific treatment plan in a series of patients with specific diseases. Phase 3 Studies: randomized comparisons (double-blind if feasible) of two or more treatment plans. Often comparison is made between a plan shown to be effective in a Phase 2 study and what is considered to be best standard treatment from previous studies. The majority of studies is directed against hematological malignancies, especially Hodgkin's disease, acute leukemia in adults, chronic lymphocytic leukemia, lymphomas, and multiple myeloma. Emphasis is now shifting toward solid tumors. Phase 1 studies are done in patients with solid tumors, and Phase 2 and 3 studies are being devised for solid tumors in which there is some evidence of effect. We deal primarily with chemotherapeutic drugs but are now incorporating the use of radiotherapy in comparison with chemotherapy or in combination with chemotherapy. Immunotherapeutic approaches are being explored. In addition to Group studies as described, ancillary studies at one or more institutions are encouraged: (1) Preliminary studies which may lead to data justifying a Group Study; (2) Basic investigations directed toward elucidating mechanism of action or other aspects of treatment given in a Group protocol; (3) Studies directed a better methods of diagnosis or classification of disease under study or better methods of evaluation of results. It is hoped that through planning, careful review of data, and sound statistical evaluation of results will lead to excellence in patient care and improve training for future physicians who will deal with the cancer patient.